Dimethyl sulfide (DMS), a biogenic trace gas emitted by marine ecosystems, plays a critical role in aerosol formation and climate regulation. However, its low atmospheric abundance and rapid reactivity hinder real-time detection, limiting our understanding of its climatic impact under warming-driven environmental changes. Here, we present a laser-based optical system using tunable infrared laser direct absorption spectroscopy (TILDAS) for the real-time DMS measurement at pptv levels. This system uses a 3.37 μm interband cascade laser and a 413.4 m multipass cell, targeting a strong DMS absorption band at 2969.7 cm⁻¹ . It achieves a detection limit of 46 pptv (3σ) with 2 min averaging of the 1 Hz data, improving to 17 pptv with 30 min averaging, verified by Allan variance analysis. Compared with existing optical DMS sensors, the system offers substantially improved sensitivity while retaining the high temporal resolution needed to resolve rapid atmospheric variability. Instrumental performance and stability were confirmed through year-round calibrations, which yielded a mean campaign-specific slope of 1.01 ± 0.02 between expected and measured DMS mixing ratios. Concurrent ambient-air measurements using TILDAS and conventional gas chromatography also showed overall agreement (slope = 1.01; r = 0.94), demonstrating reliable field performance. By combining pptv-level sensitivity, continuous 1 Hz output, minimal sample processing, and long-term operational stability, DMS-TILDAS provides a powerful tool for resolving short-timescale DMS variability, with potential future applications in marine sulfur cycling and associated aerosol and climate-related processes.
The long and varied coastline of the Korean Peninsula is home to plants that thrive in the transition zone between terrestrial and marine ecosystems. The Korean east coast, and the volcanic island of Ulleungdo facing it, is a region where species populations and lineages are allopatrically distributed, including those of the seashore spatulate aster (Aster spathulifolius Maxim.). In this study, we examined the disjunct distribution of this coastal specialist by employing genome-wide SNP markers to evaluate its genomic diversity and structure, and infer its number of independently evolving lineages in this region. Our findings suggest that the genetically distinct population structure between the peninsular and island distributions, and the significantly reduced genetic variation patterns, more so for the insular populations, appeared to be the classic signatures of the mainland-island model. The vicariant population distribution was further found to be delineated by a genetic barrier, i.e., the East Sea geographic break, although isolation by distance may have also influenced the divide. Along with the molecular line of evidence, the nomenclatural and taxonomic implications of the findings are also discussed in this paper.
Transcranial alternating current stimulation (tACS) is a noninvasive brain stimulation method that modulates neural activity by applying low-intensity alternating current to the scalp. Although tACS has shown promise in enhancing cognitive and motor functions and alleviating neuropsychiatric symptoms, variations in stimulation parameters led to inconsistent outcomes. While stimulation frequency and electrode montage have been extensively explored, systematic analyses focusing on stimulation duration remain limited. Resting-state EEG, recorded under relaxed conditions without specific tasks, minimizes variability due to individual performance and external factors, thus providing a stable measure of tACS-induced neuromodulation. Therefore, we aimed to investigate the differences in neuromodulatory effects between three tACS durations for effective neuromodulation using resting-state electroencephalography (EEG). Ten participants completed three randomized tACS sessions on different days, each with a duration of 10, 20, or 30 min. Resting-state EEG was recorded before and after stimulation under eyes-open (EO) and eyes-closed (EC) states. Power spectral density (PSD) and network indices were analyzed for neuromodulatory effects. The omnibus analysis revealed no significant main effect of stimulation duration on neuromodulatory outcomes. However, within-condition analyses revealed significant increases in PSD in the post-tACS EO recording after 10 min (r = 0.79) and 20 min (r = 0.66), whereas in the post-tACS EC recording significant increases were observed only at 10 min (r = 0.63). Network efficiency also increased significantly in the EO state after 10 (r = 0.79) and 20 min (r = 0.85) for clustering coefficient and after 10 (r = 0.73) and 20 min (r = 0.85) for path length, respectively. Moreover, the observed patterns differed between brain states, with more consistent effects observed in the EO state. These findings suggest that neuromodulatory responses may vary depending on both tACS duration and brain state, highlighting the importance of considering both factors in the design of tACS protocols and interpretation of neuromodulatory effects.
Purpose: This review aimed to summarize the recent prevalence , epidemiological characteristics of endemic parasitic in- fections in Korea as reported in the literature up to 2026. Current concepts: Data were collected from national surveillance statistics of the Korea Disease Control and Prevention Agency and from studies indexed in PubMed and KoreaMed published between January 2019 and February 2026. The overall prevalence of intestinal helminth infections has decreased substantially , infections such as ascariasis and trichuriasis (0.2%) are now rarely detected. However, clonorchiasis remains relatively prevalent in endemic river-basin regions (2.3% in 2024), reflecting persistent dietary habits involving the consumption of raw freshwater fish. Vivax malaria continues to occur near the Demilitarized Zone despite long-term control efforts (601 cases in 2025). Claims-based data showed an average of 422 cases of toxoplasmosis per year from 2007 to 2020, and the true burden may be underestimated because many infections are asymp- tomatic. Other parasitic diseases, including trichomoniasis (age- and sex-adjusted infection rate, >800 per 100,000 women aged 20-39 years in 2020) and scabies (age-adjusted infection rate, 43.0 per 100,000 in 2021), persist because of behavioral and demographic factors. Discussion and conclusion: Clonorchiasis still shows a relatively high infection rate in certain endemic areas. Malaria, toxo- plasmosis, trichomoniasis, and scabies may continue to occur because living environments and behavioral patterns are difficult to change. These parasitic diseases should be considered in the differential diagnosis in clinical practice, and patients should be evaluated with appropriate testing and referral when indicated.
Generative artificial intelligence (AI) is rapidly expanding within medical practice, yet its use among nuclear medicine professionals has not been systematically evaluated. This study provides the first society-wide assessment of generative AI adoption among members of the Korean Society of Nuclear Medicine (KSNM). An anonymous online survey was distributed to approximately 670 KSNM members. The questionnaire assessed AI use in two domains (research/education and clinical practice), including platforms, frequency, purposes, and perceived usefulness and trust. Descriptive statistics and chi-square tests were used. A total of 122 members responded (estimated response rate, 18.2
